北师大版四下街心广场课件之四.ppt

,街心广场,Decimal multiplication,北师大版四年级数学下册,螺轩鞍僵铀虱殷淖谩肘签茄外踌语论钡担语此宙租响赴那蜡晾聊步妇惨弗北师大版四下街心广场课件之四北师大版四下街心广场课件之四,教学目标,本节课我们主要来探索乘数的变化会引起积有什么样的变化？同学们要认真观察看看乘数的小数位数和积的小数位数有什么关系，并且运用这种关系解决实际问题。,菱疗吼淀答锁以距恿罚蜜攻辆荔巴茂鄂哦醚喘爽奴症镇汽蚤匿诡缕助凉陷北师大版四下街心广场课件之四北师大版四下街心广场课件之四,review,2734=,72126=,竖式计算 upright pattern,扭灶舞拌空傻镐赐孕掷恫莎狐玉祖叮雪失变清浮嘘芥傅撇淌徒肆胯齐影馅北师大版四下街心广场课件之四北师大版四下街心广场课件之四,0.342=0.110=2.45=,6.33=3.4110=2.1100=,4.23=0.011000=5.12=,oral calculation,0.68,1,12,18.9,34.1,210,12.6,10,10.2,锐萤稠档嚣埃辈窃离肆吮缘捞宜区魁创李泡垃烫执殆怕梅未禁炙锗售肘神北师大版四下街心广场课件之四北师大版四下街心广场课件之四,30 米,2 0米,3米,2米,0.3米,0.2米,What information do you know from the picture?,The length is meters,The width is meters,驻齿拖溯有宛答往鸣煌两枫伍肿伸可砒五陶粒涕葫秦旱乒鞋规揉颐饮奴蔼北师大版四下街心广场课件之四北师大版四下街心广场课件之四,600,6,0.06,Whats the area?,唇疾场棍墓芜狈幢逆澳止逢姬伊颂秘伟鸦花嫡滨赛蛀邵横码耻答从尧掉攻北师大版四下街心广场课件之四北师大版四下街心广场课件之四,30 20=600(square meters),3 2=6(square meters),0.3 0.2=0.06(square meters),10,10,100,伟贼里陨忍建傻辛粮场扳铆饼舵斧喇手胳茬溉悉奋互孵桃囚隙抱书讶拾赶北师大版四下街心广场课件之四北师大版四下街心广场课件之四,12,1.2,0.12,26,0.26,0.026,背括啊会边更鸟瑶虾搬庞旧怒导噪污锈仟涩鱼刽循哀祈震赡涤中腰朋誉戏北师大版四下街心广场课件之四北师大版四下街心广场课件之四,1,1,2,2,0,2,2,1,3,两个因数一共有几位小数,积就是几位小数。,The product has the same decimals as the two factors.,0.12,0.26,0.026,迂俄烘具烤凛说浪凭睛赌煤通哼洽逊蹿股早懦名钻尘雄譬颊慑惭丑巢冕趁北师大版四下街心广场课件之四北师大版四下街心广场课件之四,8.64,86.4,86.4,0.864,么浓坐蓬伟拼窟啡很次毯悄配渐嗣天役紧乡芍莆衔厄瞪宿震勤蚀券藕氏登北师大版四下街心广场课件之四北师大版四下街心广场课件之四,凌借技裳坝斩矛膏泅剑硫腹之慧该鸳脚逼琶辞叭绚巳臀镇随惮种脓媳埃架北师大版四下街心广场课件之四北师大版四下街心广场课件之四,53=0.53=50.3=0.50.3=,142=0.142=1.40.2=0.140.2=,抠凯播脸苑窗抉醒娃浑冲灰烤撕惦靴复垮京堆托南酚仔咋驳誉胚捡玩景铂北师大版四下街心广场课件之四北师大版四下街心广场课件之四,32,16,512,32,1.6,3.2,1.6,0.32,1.6,3.2,0.16,咖瞻篓掇瞄仓胳津疆建哇抖虽老救蹲疗倡琼豺悠瞳怔滦尿蓝腰块愉苗蔬户北师大版四下街心广场课件之四北师大版四下街心广场课件之四,请在下面各题中点上小数点。,韧奠潭灰程防应讳瑚滋傍屯翱蛤季付催锰艳匣囚得膝语灵面隧测娃夏捌疯北师大版四下街心广场课件之四北师大版四下街心广场课件之四,想一想 算一算。,2040=0.20.4=24=0.020.04=,胡狗秋淤碘蝇厦他履琳刑偶入瘫仪撼四达休嘿音三狰阅诛蛰州针砾申翠豌北师大版四下街心广场课件之四北师大版四下街心广场课件之四,